![Steffen Klassert](/assets/img/avatar_default.png)
Add get_online_cpus/put_online_cpus to ensure that no cpu goes offline during the flushing of the padata percpu queues. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
775 lines
17 KiB
C
775 lines
17 KiB
C
/*
|
|
* padata.c - generic interface to process data streams in parallel
|
|
*
|
|
* Copyright (C) 2008, 2009 secunet Security Networks AG
|
|
* Copyright (C) 2008, 2009 Steffen Klassert <steffen.klassert@secunet.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms and conditions of the GNU General Public License,
|
|
* version 2, as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
* more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along with
|
|
* this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/cpumask.h>
|
|
#include <linux/err.h>
|
|
#include <linux/cpu.h>
|
|
#include <linux/padata.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/rcupdate.h>
|
|
|
|
#define MAX_SEQ_NR INT_MAX - NR_CPUS
|
|
#define MAX_OBJ_NUM 1000
|
|
|
|
static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
|
|
{
|
|
int cpu, target_cpu;
|
|
|
|
target_cpu = cpumask_first(pd->cpumask);
|
|
for (cpu = 0; cpu < cpu_index; cpu++)
|
|
target_cpu = cpumask_next(target_cpu, pd->cpumask);
|
|
|
|
return target_cpu;
|
|
}
|
|
|
|
static int padata_cpu_hash(struct padata_priv *padata)
|
|
{
|
|
int cpu_index;
|
|
struct parallel_data *pd;
|
|
|
|
pd = padata->pd;
|
|
|
|
/*
|
|
* Hash the sequence numbers to the cpus by taking
|
|
* seq_nr mod. number of cpus in use.
|
|
*/
|
|
cpu_index = padata->seq_nr % cpumask_weight(pd->cpumask);
|
|
|
|
return padata_index_to_cpu(pd, cpu_index);
|
|
}
|
|
|
|
static void padata_parallel_worker(struct work_struct *work)
|
|
{
|
|
struct padata_queue *queue;
|
|
struct parallel_data *pd;
|
|
struct padata_instance *pinst;
|
|
LIST_HEAD(local_list);
|
|
|
|
local_bh_disable();
|
|
queue = container_of(work, struct padata_queue, pwork);
|
|
pd = queue->pd;
|
|
pinst = pd->pinst;
|
|
|
|
spin_lock(&queue->parallel.lock);
|
|
list_replace_init(&queue->parallel.list, &local_list);
|
|
spin_unlock(&queue->parallel.lock);
|
|
|
|
while (!list_empty(&local_list)) {
|
|
struct padata_priv *padata;
|
|
|
|
padata = list_entry(local_list.next,
|
|
struct padata_priv, list);
|
|
|
|
list_del_init(&padata->list);
|
|
|
|
padata->parallel(padata);
|
|
}
|
|
|
|
local_bh_enable();
|
|
}
|
|
|
|
/**
|
|
* padata_do_parallel - padata parallelization function
|
|
*
|
|
* @pinst: padata instance
|
|
* @padata: object to be parallelized
|
|
* @cb_cpu: cpu the serialization callback function will run on,
|
|
* must be in the cpumask of padata.
|
|
*
|
|
* The parallelization callback function will run with BHs off.
|
|
* Note: Every object which is parallelized by padata_do_parallel
|
|
* must be seen by padata_do_serial.
|
|
*/
|
|
int padata_do_parallel(struct padata_instance *pinst,
|
|
struct padata_priv *padata, int cb_cpu)
|
|
{
|
|
int target_cpu, err;
|
|
struct padata_queue *queue;
|
|
struct parallel_data *pd;
|
|
|
|
rcu_read_lock_bh();
|
|
|
|
pd = rcu_dereference(pinst->pd);
|
|
|
|
err = 0;
|
|
if (!(pinst->flags & PADATA_INIT))
|
|
goto out;
|
|
|
|
err = -EBUSY;
|
|
if ((pinst->flags & PADATA_RESET))
|
|
goto out;
|
|
|
|
if (atomic_read(&pd->refcnt) >= MAX_OBJ_NUM)
|
|
goto out;
|
|
|
|
err = -EINVAL;
|
|
if (!cpumask_test_cpu(cb_cpu, pd->cpumask))
|
|
goto out;
|
|
|
|
err = -EINPROGRESS;
|
|
atomic_inc(&pd->refcnt);
|
|
padata->pd = pd;
|
|
padata->cb_cpu = cb_cpu;
|
|
|
|
if (unlikely(atomic_read(&pd->seq_nr) == pd->max_seq_nr))
|
|
atomic_set(&pd->seq_nr, -1);
|
|
|
|
padata->seq_nr = atomic_inc_return(&pd->seq_nr);
|
|
|
|
target_cpu = padata_cpu_hash(padata);
|
|
queue = per_cpu_ptr(pd->queue, target_cpu);
|
|
|
|
spin_lock(&queue->parallel.lock);
|
|
list_add_tail(&padata->list, &queue->parallel.list);
|
|
spin_unlock(&queue->parallel.lock);
|
|
|
|
queue_work_on(target_cpu, pinst->wq, &queue->pwork);
|
|
|
|
out:
|
|
rcu_read_unlock_bh();
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(padata_do_parallel);
|
|
|
|
/*
|
|
* padata_get_next - Get the next object that needs serialization.
|
|
*
|
|
* Return values are:
|
|
*
|
|
* A pointer to the control struct of the next object that needs
|
|
* serialization, if present in one of the percpu reorder queues.
|
|
*
|
|
* NULL, if all percpu reorder queues are empty.
|
|
*
|
|
* -EINPROGRESS, if the next object that needs serialization will
|
|
* be parallel processed by another cpu and is not yet present in
|
|
* the cpu's reorder queue.
|
|
*
|
|
* -ENODATA, if this cpu has to do the parallel processing for
|
|
* the next object.
|
|
*/
|
|
static struct padata_priv *padata_get_next(struct parallel_data *pd)
|
|
{
|
|
int cpu, num_cpus, empty, calc_seq_nr;
|
|
int seq_nr, next_nr, overrun, next_overrun;
|
|
struct padata_queue *queue, *next_queue;
|
|
struct padata_priv *padata;
|
|
struct padata_list *reorder;
|
|
|
|
empty = 0;
|
|
next_nr = -1;
|
|
next_overrun = 0;
|
|
next_queue = NULL;
|
|
|
|
num_cpus = cpumask_weight(pd->cpumask);
|
|
|
|
for_each_cpu(cpu, pd->cpumask) {
|
|
queue = per_cpu_ptr(pd->queue, cpu);
|
|
reorder = &queue->reorder;
|
|
|
|
/*
|
|
* Calculate the seq_nr of the object that should be
|
|
* next in this reorder queue.
|
|
*/
|
|
overrun = 0;
|
|
calc_seq_nr = (atomic_read(&queue->num_obj) * num_cpus)
|
|
+ queue->cpu_index;
|
|
|
|
if (unlikely(calc_seq_nr > pd->max_seq_nr)) {
|
|
calc_seq_nr = calc_seq_nr - pd->max_seq_nr - 1;
|
|
overrun = 1;
|
|
}
|
|
|
|
if (!list_empty(&reorder->list)) {
|
|
padata = list_entry(reorder->list.next,
|
|
struct padata_priv, list);
|
|
|
|
seq_nr = padata->seq_nr;
|
|
BUG_ON(calc_seq_nr != seq_nr);
|
|
} else {
|
|
seq_nr = calc_seq_nr;
|
|
empty++;
|
|
}
|
|
|
|
if (next_nr < 0 || seq_nr < next_nr
|
|
|| (next_overrun && !overrun)) {
|
|
next_nr = seq_nr;
|
|
next_overrun = overrun;
|
|
next_queue = queue;
|
|
}
|
|
}
|
|
|
|
padata = NULL;
|
|
|
|
if (empty == num_cpus)
|
|
goto out;
|
|
|
|
reorder = &next_queue->reorder;
|
|
|
|
if (!list_empty(&reorder->list)) {
|
|
padata = list_entry(reorder->list.next,
|
|
struct padata_priv, list);
|
|
|
|
if (unlikely(next_overrun)) {
|
|
for_each_cpu(cpu, pd->cpumask) {
|
|
queue = per_cpu_ptr(pd->queue, cpu);
|
|
atomic_set(&queue->num_obj, 0);
|
|
}
|
|
}
|
|
|
|
spin_lock(&reorder->lock);
|
|
list_del_init(&padata->list);
|
|
atomic_dec(&pd->reorder_objects);
|
|
spin_unlock(&reorder->lock);
|
|
|
|
atomic_inc(&next_queue->num_obj);
|
|
|
|
goto out;
|
|
}
|
|
|
|
queue = per_cpu_ptr(pd->queue, smp_processor_id());
|
|
if (queue->cpu_index == next_queue->cpu_index) {
|
|
padata = ERR_PTR(-ENODATA);
|
|
goto out;
|
|
}
|
|
|
|
padata = ERR_PTR(-EINPROGRESS);
|
|
out:
|
|
return padata;
|
|
}
|
|
|
|
static void padata_reorder(struct parallel_data *pd)
|
|
{
|
|
struct padata_priv *padata;
|
|
struct padata_queue *queue;
|
|
struct padata_instance *pinst = pd->pinst;
|
|
|
|
/*
|
|
* We need to ensure that only one cpu can work on dequeueing of
|
|
* the reorder queue the time. Calculating in which percpu reorder
|
|
* queue the next object will arrive takes some time. A spinlock
|
|
* would be highly contended. Also it is not clear in which order
|
|
* the objects arrive to the reorder queues. So a cpu could wait to
|
|
* get the lock just to notice that there is nothing to do at the
|
|
* moment. Therefore we use a trylock and let the holder of the lock
|
|
* care for all the objects enqueued during the holdtime of the lock.
|
|
*/
|
|
if (!spin_trylock_bh(&pd->lock))
|
|
return;
|
|
|
|
while (1) {
|
|
padata = padata_get_next(pd);
|
|
|
|
/*
|
|
* All reorder queues are empty, or the next object that needs
|
|
* serialization is parallel processed by another cpu and is
|
|
* still on it's way to the cpu's reorder queue, nothing to
|
|
* do for now.
|
|
*/
|
|
if (!padata || PTR_ERR(padata) == -EINPROGRESS)
|
|
break;
|
|
|
|
/*
|
|
* This cpu has to do the parallel processing of the next
|
|
* object. It's waiting in the cpu's parallelization queue,
|
|
* so exit imediately.
|
|
*/
|
|
if (PTR_ERR(padata) == -ENODATA) {
|
|
del_timer(&pd->timer);
|
|
spin_unlock_bh(&pd->lock);
|
|
return;
|
|
}
|
|
|
|
queue = per_cpu_ptr(pd->queue, padata->cb_cpu);
|
|
|
|
spin_lock(&queue->serial.lock);
|
|
list_add_tail(&padata->list, &queue->serial.list);
|
|
spin_unlock(&queue->serial.lock);
|
|
|
|
queue_work_on(padata->cb_cpu, pinst->wq, &queue->swork);
|
|
}
|
|
|
|
spin_unlock_bh(&pd->lock);
|
|
|
|
/*
|
|
* The next object that needs serialization might have arrived to
|
|
* the reorder queues in the meantime, we will be called again
|
|
* from the timer function if noone else cares for it.
|
|
*/
|
|
if (atomic_read(&pd->reorder_objects)
|
|
&& !(pinst->flags & PADATA_RESET))
|
|
mod_timer(&pd->timer, jiffies + HZ);
|
|
else
|
|
del_timer(&pd->timer);
|
|
|
|
return;
|
|
}
|
|
|
|
static void padata_reorder_timer(unsigned long arg)
|
|
{
|
|
struct parallel_data *pd = (struct parallel_data *)arg;
|
|
|
|
padata_reorder(pd);
|
|
}
|
|
|
|
static void padata_serial_worker(struct work_struct *work)
|
|
{
|
|
struct padata_queue *queue;
|
|
struct parallel_data *pd;
|
|
LIST_HEAD(local_list);
|
|
|
|
local_bh_disable();
|
|
queue = container_of(work, struct padata_queue, swork);
|
|
pd = queue->pd;
|
|
|
|
spin_lock(&queue->serial.lock);
|
|
list_replace_init(&queue->serial.list, &local_list);
|
|
spin_unlock(&queue->serial.lock);
|
|
|
|
while (!list_empty(&local_list)) {
|
|
struct padata_priv *padata;
|
|
|
|
padata = list_entry(local_list.next,
|
|
struct padata_priv, list);
|
|
|
|
list_del_init(&padata->list);
|
|
|
|
padata->serial(padata);
|
|
atomic_dec(&pd->refcnt);
|
|
}
|
|
local_bh_enable();
|
|
}
|
|
|
|
/**
|
|
* padata_do_serial - padata serialization function
|
|
*
|
|
* @padata: object to be serialized.
|
|
*
|
|
* padata_do_serial must be called for every parallelized object.
|
|
* The serialization callback function will run with BHs off.
|
|
*/
|
|
void padata_do_serial(struct padata_priv *padata)
|
|
{
|
|
int cpu;
|
|
struct padata_queue *queue;
|
|
struct parallel_data *pd;
|
|
|
|
pd = padata->pd;
|
|
|
|
cpu = get_cpu();
|
|
queue = per_cpu_ptr(pd->queue, cpu);
|
|
|
|
spin_lock(&queue->reorder.lock);
|
|
atomic_inc(&pd->reorder_objects);
|
|
list_add_tail(&padata->list, &queue->reorder.list);
|
|
spin_unlock(&queue->reorder.lock);
|
|
|
|
put_cpu();
|
|
|
|
padata_reorder(pd);
|
|
}
|
|
EXPORT_SYMBOL(padata_do_serial);
|
|
|
|
/* Allocate and initialize the internal cpumask dependend resources. */
|
|
static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
|
|
const struct cpumask *cpumask)
|
|
{
|
|
int cpu, cpu_index, num_cpus;
|
|
struct padata_queue *queue;
|
|
struct parallel_data *pd;
|
|
|
|
cpu_index = 0;
|
|
|
|
pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL);
|
|
if (!pd)
|
|
goto err;
|
|
|
|
pd->queue = alloc_percpu(struct padata_queue);
|
|
if (!pd->queue)
|
|
goto err_free_pd;
|
|
|
|
if (!alloc_cpumask_var(&pd->cpumask, GFP_KERNEL))
|
|
goto err_free_queue;
|
|
|
|
cpumask_and(pd->cpumask, cpumask, cpu_active_mask);
|
|
|
|
for_each_cpu(cpu, pd->cpumask) {
|
|
queue = per_cpu_ptr(pd->queue, cpu);
|
|
|
|
queue->pd = pd;
|
|
|
|
queue->cpu_index = cpu_index;
|
|
cpu_index++;
|
|
|
|
INIT_LIST_HEAD(&queue->reorder.list);
|
|
INIT_LIST_HEAD(&queue->parallel.list);
|
|
INIT_LIST_HEAD(&queue->serial.list);
|
|
spin_lock_init(&queue->reorder.lock);
|
|
spin_lock_init(&queue->parallel.lock);
|
|
spin_lock_init(&queue->serial.lock);
|
|
|
|
INIT_WORK(&queue->pwork, padata_parallel_worker);
|
|
INIT_WORK(&queue->swork, padata_serial_worker);
|
|
atomic_set(&queue->num_obj, 0);
|
|
}
|
|
|
|
num_cpus = cpumask_weight(pd->cpumask);
|
|
pd->max_seq_nr = (MAX_SEQ_NR / num_cpus) * num_cpus - 1;
|
|
|
|
setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd);
|
|
atomic_set(&pd->seq_nr, -1);
|
|
atomic_set(&pd->reorder_objects, 0);
|
|
atomic_set(&pd->refcnt, 0);
|
|
pd->pinst = pinst;
|
|
spin_lock_init(&pd->lock);
|
|
|
|
return pd;
|
|
|
|
err_free_queue:
|
|
free_percpu(pd->queue);
|
|
err_free_pd:
|
|
kfree(pd);
|
|
err:
|
|
return NULL;
|
|
}
|
|
|
|
static void padata_free_pd(struct parallel_data *pd)
|
|
{
|
|
free_cpumask_var(pd->cpumask);
|
|
free_percpu(pd->queue);
|
|
kfree(pd);
|
|
}
|
|
|
|
/* Flush all objects out of the padata queues. */
|
|
static void padata_flush_queues(struct parallel_data *pd)
|
|
{
|
|
int cpu;
|
|
struct padata_queue *queue;
|
|
|
|
for_each_cpu(cpu, pd->cpumask) {
|
|
queue = per_cpu_ptr(pd->queue, cpu);
|
|
flush_work(&queue->pwork);
|
|
}
|
|
|
|
del_timer_sync(&pd->timer);
|
|
|
|
if (atomic_read(&pd->reorder_objects))
|
|
padata_reorder(pd);
|
|
|
|
for_each_cpu(cpu, pd->cpumask) {
|
|
queue = per_cpu_ptr(pd->queue, cpu);
|
|
flush_work(&queue->swork);
|
|
}
|
|
|
|
BUG_ON(atomic_read(&pd->refcnt) != 0);
|
|
}
|
|
|
|
/* Replace the internal control stucture with a new one. */
|
|
static void padata_replace(struct padata_instance *pinst,
|
|
struct parallel_data *pd_new)
|
|
{
|
|
struct parallel_data *pd_old = pinst->pd;
|
|
|
|
pinst->flags |= PADATA_RESET;
|
|
|
|
rcu_assign_pointer(pinst->pd, pd_new);
|
|
|
|
synchronize_rcu();
|
|
|
|
padata_flush_queues(pd_old);
|
|
padata_free_pd(pd_old);
|
|
|
|
pinst->flags &= ~PADATA_RESET;
|
|
}
|
|
|
|
/**
|
|
* padata_set_cpumask - set the cpumask that padata should use
|
|
*
|
|
* @pinst: padata instance
|
|
* @cpumask: the cpumask to use
|
|
*/
|
|
int padata_set_cpumask(struct padata_instance *pinst,
|
|
cpumask_var_t cpumask)
|
|
{
|
|
struct parallel_data *pd;
|
|
int err = 0;
|
|
|
|
mutex_lock(&pinst->lock);
|
|
|
|
get_online_cpus();
|
|
|
|
pd = padata_alloc_pd(pinst, cpumask);
|
|
if (!pd) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
cpumask_copy(pinst->cpumask, cpumask);
|
|
|
|
padata_replace(pinst, pd);
|
|
|
|
out:
|
|
put_online_cpus();
|
|
|
|
mutex_unlock(&pinst->lock);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(padata_set_cpumask);
|
|
|
|
static int __padata_add_cpu(struct padata_instance *pinst, int cpu)
|
|
{
|
|
struct parallel_data *pd;
|
|
|
|
if (cpumask_test_cpu(cpu, cpu_active_mask)) {
|
|
pd = padata_alloc_pd(pinst, pinst->cpumask);
|
|
if (!pd)
|
|
return -ENOMEM;
|
|
|
|
padata_replace(pinst, pd);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* padata_add_cpu - add a cpu to the padata cpumask
|
|
*
|
|
* @pinst: padata instance
|
|
* @cpu: cpu to add
|
|
*/
|
|
int padata_add_cpu(struct padata_instance *pinst, int cpu)
|
|
{
|
|
int err;
|
|
|
|
mutex_lock(&pinst->lock);
|
|
|
|
get_online_cpus();
|
|
cpumask_set_cpu(cpu, pinst->cpumask);
|
|
err = __padata_add_cpu(pinst, cpu);
|
|
put_online_cpus();
|
|
|
|
mutex_unlock(&pinst->lock);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(padata_add_cpu);
|
|
|
|
static int __padata_remove_cpu(struct padata_instance *pinst, int cpu)
|
|
{
|
|
struct parallel_data *pd;
|
|
|
|
if (cpumask_test_cpu(cpu, cpu_online_mask)) {
|
|
pd = padata_alloc_pd(pinst, pinst->cpumask);
|
|
if (!pd)
|
|
return -ENOMEM;
|
|
|
|
padata_replace(pinst, pd);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* padata_remove_cpu - remove a cpu from the padata cpumask
|
|
*
|
|
* @pinst: padata instance
|
|
* @cpu: cpu to remove
|
|
*/
|
|
int padata_remove_cpu(struct padata_instance *pinst, int cpu)
|
|
{
|
|
int err;
|
|
|
|
mutex_lock(&pinst->lock);
|
|
|
|
get_online_cpus();
|
|
cpumask_clear_cpu(cpu, pinst->cpumask);
|
|
err = __padata_remove_cpu(pinst, cpu);
|
|
put_online_cpus();
|
|
|
|
mutex_unlock(&pinst->lock);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(padata_remove_cpu);
|
|
|
|
/**
|
|
* padata_start - start the parallel processing
|
|
*
|
|
* @pinst: padata instance to start
|
|
*/
|
|
void padata_start(struct padata_instance *pinst)
|
|
{
|
|
mutex_lock(&pinst->lock);
|
|
pinst->flags |= PADATA_INIT;
|
|
mutex_unlock(&pinst->lock);
|
|
}
|
|
EXPORT_SYMBOL(padata_start);
|
|
|
|
/**
|
|
* padata_stop - stop the parallel processing
|
|
*
|
|
* @pinst: padata instance to stop
|
|
*/
|
|
void padata_stop(struct padata_instance *pinst)
|
|
{
|
|
mutex_lock(&pinst->lock);
|
|
pinst->flags &= ~PADATA_INIT;
|
|
mutex_unlock(&pinst->lock);
|
|
}
|
|
EXPORT_SYMBOL(padata_stop);
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
static int padata_cpu_callback(struct notifier_block *nfb,
|
|
unsigned long action, void *hcpu)
|
|
{
|
|
int err;
|
|
struct padata_instance *pinst;
|
|
int cpu = (unsigned long)hcpu;
|
|
|
|
pinst = container_of(nfb, struct padata_instance, cpu_notifier);
|
|
|
|
switch (action) {
|
|
case CPU_ONLINE:
|
|
case CPU_ONLINE_FROZEN:
|
|
if (!cpumask_test_cpu(cpu, pinst->cpumask))
|
|
break;
|
|
mutex_lock(&pinst->lock);
|
|
err = __padata_add_cpu(pinst, cpu);
|
|
mutex_unlock(&pinst->lock);
|
|
if (err)
|
|
return NOTIFY_BAD;
|
|
break;
|
|
|
|
case CPU_DOWN_PREPARE:
|
|
case CPU_DOWN_PREPARE_FROZEN:
|
|
if (!cpumask_test_cpu(cpu, pinst->cpumask))
|
|
break;
|
|
mutex_lock(&pinst->lock);
|
|
err = __padata_remove_cpu(pinst, cpu);
|
|
mutex_unlock(&pinst->lock);
|
|
if (err)
|
|
return NOTIFY_BAD;
|
|
break;
|
|
|
|
case CPU_UP_CANCELED:
|
|
case CPU_UP_CANCELED_FROZEN:
|
|
if (!cpumask_test_cpu(cpu, pinst->cpumask))
|
|
break;
|
|
mutex_lock(&pinst->lock);
|
|
__padata_remove_cpu(pinst, cpu);
|
|
mutex_unlock(&pinst->lock);
|
|
|
|
case CPU_DOWN_FAILED:
|
|
case CPU_DOWN_FAILED_FROZEN:
|
|
if (!cpumask_test_cpu(cpu, pinst->cpumask))
|
|
break;
|
|
mutex_lock(&pinst->lock);
|
|
__padata_add_cpu(pinst, cpu);
|
|
mutex_unlock(&pinst->lock);
|
|
}
|
|
|
|
return NOTIFY_OK;
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* padata_alloc - allocate and initialize a padata instance
|
|
*
|
|
* @cpumask: cpumask that padata uses for parallelization
|
|
* @wq: workqueue to use for the allocated padata instance
|
|
*/
|
|
struct padata_instance *padata_alloc(const struct cpumask *cpumask,
|
|
struct workqueue_struct *wq)
|
|
{
|
|
struct padata_instance *pinst;
|
|
struct parallel_data *pd;
|
|
|
|
pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL);
|
|
if (!pinst)
|
|
goto err;
|
|
|
|
get_online_cpus();
|
|
|
|
pd = padata_alloc_pd(pinst, cpumask);
|
|
if (!pd)
|
|
goto err_free_inst;
|
|
|
|
if (!alloc_cpumask_var(&pinst->cpumask, GFP_KERNEL))
|
|
goto err_free_pd;
|
|
|
|
rcu_assign_pointer(pinst->pd, pd);
|
|
|
|
pinst->wq = wq;
|
|
|
|
cpumask_copy(pinst->cpumask, cpumask);
|
|
|
|
pinst->flags = 0;
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
pinst->cpu_notifier.notifier_call = padata_cpu_callback;
|
|
pinst->cpu_notifier.priority = 0;
|
|
register_hotcpu_notifier(&pinst->cpu_notifier);
|
|
#endif
|
|
|
|
put_online_cpus();
|
|
|
|
mutex_init(&pinst->lock);
|
|
|
|
return pinst;
|
|
|
|
err_free_pd:
|
|
padata_free_pd(pd);
|
|
err_free_inst:
|
|
kfree(pinst);
|
|
put_online_cpus();
|
|
err:
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(padata_alloc);
|
|
|
|
/**
|
|
* padata_free - free a padata instance
|
|
*
|
|
* @padata_inst: padata instance to free
|
|
*/
|
|
void padata_free(struct padata_instance *pinst)
|
|
{
|
|
padata_stop(pinst);
|
|
|
|
synchronize_rcu();
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
unregister_hotcpu_notifier(&pinst->cpu_notifier);
|
|
#endif
|
|
get_online_cpus();
|
|
padata_flush_queues(pinst->pd);
|
|
put_online_cpus();
|
|
|
|
padata_free_pd(pinst->pd);
|
|
free_cpumask_var(pinst->cpumask);
|
|
kfree(pinst);
|
|
}
|
|
EXPORT_SYMBOL(padata_free);
|